Conventionally, beverages are dispensed into drinking vessels simply by pouring the beverage into the mouth of the vessel. Draught beer, for example, is generally dispensed from a beer tap directly into the mouth of a beer glass.
Most beers are carbonated with carbon dioxide. The carbon dioxide dissolved in the beer is what makes the beer fizzy. When beer is poured into a glass from a beer tap, the agitation of pouring and the turbulence created by the stream of beer hitting the bottom of the glass as it falls from the tap causes some of the carbon dioxide to bubble out of solution, forming a head of foam on the glass of beer. However, if the beer is dispensed by someone who is not particularly skilled in the art of beer pouring, an excessive head of foam may be formed on the upper surface of the beer. This may also occur when pouring carbonated soft drinks.
Other beers, such as stouts, are less fizzy than carbonated lager beers, as they contain less dissolved carbon dioxide. However, these beers, once poured, require “settling time” to allow the turbulence created in the beer during pouring to subside and to allow a creamy head to form on the beer. The time involved in correctly pouring a glass of stout can be up to three minutes, including settling time.
It is therefore desirable to allow beverages such as beer to be dispensed in a such a way that the turbulence and agitation created in the beverage during dispensing is reduced, thereby making correct dispensing of the beverage easier and reducing settling time required. A number of techniques have been proposed.
British Patent No. GB2353785 describes a nozzle for a beer dispenser, which is inserted into a beer glass to dispense beer near the bottom of the glass. The nozzle is operated by pressing the bottom of the glass upwards against a spring bias to open apertures in the nozzle.
British Patent No. GB2178003 relates to a method of dispensing beer at the bottom of a glass and describes a dispensing nozzle is adapted to reach the bottom of the glass.
British Patent No. GB2322691 relates to a beverage dispenser with a long outlet spout, which in use extends to the bottom of a glass into which the beverage is to be dispensed. Beverage is dispensed when the end of the spout is pressed against the bottom of the glass.
One problem associated with these arrangements is that a nozzle must be inserted into the glass so that it extends to the bottom thereof. The nozzle is thus immersed in the beer in the glass. When the next glass of beer is dispensed, the nozzle, along with its coating of stale beer, is inserted into the new glass, which could be unhygienic.